This chapter describes the digital signature schemes implemented in GNU
Crypto. The package for all signature and related classes is
gnu.crypto.sig. The following signature schemes are implemented:

DSS, the Digital Signature Standard, was standardized in 1994 by the
National Institute of Standards and Technology in the Federal
Information Processing Standards (FIPS) Publication 186 [FIPS186]. DSS
uses the secure hash algorithm (SHA-1) internally, and produces a 160
bit signature.

RSA-PSS. This is a digital signature scheme based on the combination
of the RSA algorithm with the Probabilistic Signature Scheme (PSS)
encoding scheme. RSA was invented by Ron Rivest, Adi Shamir, and Leonard
Adleman; the PSS encoding was developed by Mihir Bellare and Phillip
Rogaway. During efforts to adopt RSA-PSS into the IEEE P1363a standards
effort, certain adaptations to the original version of RSA-PSS were made
by Mihir Bellare and Phillip Rogaway and also by Burt Kaliski (the
editor of IEEE P1363a) to facilitate implementation and integration into
existing protocols. [JoK00]